1. Field of the Invention
The present invention relates to a storage device connected through an internal network to an external network, a storage system having the storage device, and the control thereof.
2. Description of Related Art
A protocol such as a Server Message Block (SMB) protocol is used to share files of Network Attached Storage (NAS) connected to a Local Area Network (LAN). In addition, a protocol such as a File Transfer Protocol (FTP) is used to transfer files from NAS to the Internet.
Japanese Patent Application Laid-open No. 2005-301809 describes uploading of data files from a data transfer device to an FTP server, and downloading of data files from the FTP server to a different data transfer device.
In the case a network address that is only valid on an LAN is imparted to an NAS, even if that NAS is attempted to be accessed from an external terminal connected to a different LAN or the Internet, that NAS cannot be accessed unless a network exchange is specially set. In addition, even if a firewall is provided between an LAN and the Internet, the NAS cannot be accessed from an external terminal unless a firewall is specially set.